With the onset of regulations such as USP 797 and USP 800, it can be challenging to test filter systems, e.g., during required certification activities, where accessibility is limited or an HVAC system does not allow feeding of the aerosol (smoke) through the system. This challenge now reaches from the big Pharmaceutical world to the everyday world of Compounding Pharmacies, and to small neighborhood pharmacies. Most of these small remote clean spaces add either terminal HEPA filters or in most cases Fan Filter Units since they are adding these filters into an existing system that does not have the capacity to accommodate the resistance of HEPA filtration. This is a problem that faces certification companies throughout the world.